Process of making an article for dissolution upon use to deliver surfactants

ABSTRACT

A process that results in a flexible dissolvable porous solid article that can be used as a personal care composition or a fabric care composition.

FIELD OF THE INVENTION

The present invention relates to a process for making a flexible porousdissolvable solid structure article useful as a personal care product.

BACKGROUND OF THE INVENTION

Dissolvable personal care films are known comprising a water-solublepolymeric structurant and a surfactant or other active ingredient.However, in order to achieve the requisite rapid dissolution ratesneeded for consumer convenience, these films are generally on the orderof less than 100 microns thickness (typically 50 microns) and, thereby,are generally of too low a basis weight (typically 50-100 grams of solidper square meter) to enable feasible consumer application of asufficient dosage of active ingredients for entire body or whole headhair application and performance, i.e., beyond lower dosage applicationssuch as hand cleansing and/or the facial applications.

Dissolvable porous solid personal care products have been taughtcomprising natural starch and surfactants (See US 2004/0048759).However, these porous solids were produced by an anhydrous extrusionprocess and employing volatile blowing agents to produce the cellularstructure via high pressure drop induced expansion of the solid. Theanhydrous process limits the components available to anhydrous materialssuch as solid-sourced surfactants which are unacceptably harsh to skin,hair and fabric surfaces and are known for “skin” formation due to thepartial collapse of structure after the abrupt high pressure drop at theexit of the extruder die also termed “shrinkage”. Such skins areunacceptable as these would serve as a barrier for water ingress to theinterior and adversely affect dissolution rates.

Freeze-dried open-celled porous solids for personal care have beentaught (See U.S. Pat. No. 6,106,849 and US 2007/0225388). However, suchresulting freeze-dried porous solids are rigid, brittle and fragile andwithout plasticization of the polymer such that it remains in its glassystate to avoid collapse of the structure during the process (See U.S.Pat. No. 5,457,895 Kearney P. et. al., issued 1995). Also, freeze-dryingis a relatively high energy and costly process.

Therefore a need exists for a process that results in a desiredflexible, dissolvable porous solid structure which can be easily andquickly manufactured that gives the desired properties of flexibility,dissolution, surfactant dosing levels and lather by consumers utilizingsuch articles.

SUMMARY OF THE INVENTION

The present invention relates to a process for preparing a flexibleporous dissolvable solid structure article, comprising the steps of:Preparing a pre-mixture comprising surfactant, water soluble polymer,and optionally plasticizer, wherein said pre-mixture comprises: fromabout 15% to 70% solids; and a viscosity of from about 2,500 cps to150,000 cps; aerating said pre-mixture by introducing a gas into thepre-mixture to form a wet aerated pre-mixture; forming the wet aeratedpre-mixture into a desired one or more shapes to formed aerated wetpre-mixture; and drying the formed aerated wet pre-mixture in a dryingenvironment, wherein the drying environment is heated, such that thepre-mix is dried within about 3 minutes to about 90 minutes to a finalmoisture content from about 0.1% to about 25% moisture to form theflexible dissolvable porous solid structure article.

The present invention further relates to a process for preparing aporous dissolvable solid structure article, comprising the steps of:preparing a pre-mixture comprising surfactant, water soluble polymer,and optionally plasticizer, wherein said pre-mixture comprises: fromabout 30% to 70% solids; and ii. a viscosity of from about 15,000 cps to150,000 cps; heating the pre-mixture between about 40° C. and about 99°C.; aerating said pre-mixture by introducing a gas into the pre-mixtureto form a wet aerated pre-mixture; forming the wet aerated pre-mixtureinto a desired one or more shapes to formed aerated wet pre-mixture; anddrying the shaped wet pre-mix to a dry density of from about 0.10 g/cm³to about 0.40 g/cm³, to form the porous dissolvable solid structurearticle.

The present invention further relates to a process for preparing aflexible porous dissolvable solid structure article, comprising thesteps of: Preparing a pre-mixture comprising surfactant, water solublepolymer, and optionally plasticizer, wherein said pre-mixture comprises:from about 30% to 70% solids; and a viscosity of from about 15,000 cpsto 150,000; aerating said pre-mixture by introducing a gas into thepre-mixture to form a wet aerated pre-mixture; forming the wet aeratedpre-mixture into a desired one or more shapes to formed aerated wetpre-mixture; and drying the formed aerated wet pre-mixture in a dryingenvironment, wherein the drying environment is heated to a temperaturebetween 100° C. and 150° C., such that the pre-mix is dried to a finalmoisture content from about 0.1% to about 25% moisture to form theflexible dissolvable porous solid structure article.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a SEM Images of Example 13.1;

FIG. 1 b SEM Images of Example 13.3;

FIG. 1 c SEM Images of Example 14.1;

FIG. 1 d SEM Images of Example 14.3;

FIG. 1 e SEM Images of Example 15.1;

FIG. 1 f SEM Images of Example 15.3;

FIG. 2 a Micro-CT Images of Example 13.1;

FIG. 2 b Micro-CT Images of Example 13.3;

FIG. 2 c Micro-CT Images of Example 14.1;

FIG. 2 d Micro-CT Images of Example 14.3;

FIG. 2 e Micro-CT Images of Example 15.1;

FIG. 2 f Micro-CT Images of Example 15.3;

FIG. 3 a Micro-CT Images of Example 13.2;

FIG. 3 b Micro-CT Images of Example 13.4;

FIG. 3 c Micro-CT Images of Example 14.2;

FIG. 3 d Micro-CT Images of Example 14.4;

FIG. 3 e Micro-CT Images of Example 15.2;

FIG. 3 f Micro-CT Images of Example 15.4;

FIG. 4 a SEM Images of Example 21.1;

FIG. 4 b SEM Images of Example 21.2;

FIG. 4 c SEM Images of Example 22;

FIG. 4 d SEM Images of Example 24;

FIG. 5 a Micro-CT Images of Example 21.1;

FIG. 5 b Micro-CT Images of Example 21.2;

FIG. 5 c Micro-CT Images of Example 22;

FIG. 5 d Micro-CT Images of Example 24;

FIG. 6 a SEM Images of Example 14.1;

FIG. 6 b SEM Images of Example 27;

FIG. 7 a Micro-CT Images of Example 14.1;

FIG. 7 b Micro-CT Images of Example 27.

DETAILED DESCRIPTION OF THE INVENTION

The flexible porous dissolvable solid structure article may be referredto herein as “the Article” or “the Dissolvable Article”. All referencesare intended to mean the flexible dissolvable porous solid structurearticle.

As used herein, “flexible” means that the porous dissolvable solidstructure article meets the distance to maximum force values discussedherein.

The Article has a distance to maximum force value of from about 6 mm toabout 30 mm, in one embodiment from about 7 mm to about 25 mm, inanother embodiment from about 8 mm to about 20 mm, and in still anotherembodiment from about 9 mm to about 15 mm as measured by the Distance toMaximum Force Method.

As used herein, “dissolvable” means that the flexible porous dissolvablesolid structure article meets the hand dissolution value. The Articlehas a hand dissolution value of from about 1 to about 30 strokes, in oneembodiment from about 2 to about 25 strokes, in another embodiment fromabout 3 to about 20 strokes, and in still another embodiment from about4 to about 15 strokes as measured by the Hand Dissolution Method.

As used herein “porous solid structure” means a solid, interconnected,polymer-containing matrix that defines a network of spaces or cells thatcontain a gas, typically a gas such as air without collapse of the foamstructure during the drying process, thereby maintaining the physicalstrength and cohesiveness of the solid. The interconnectivity of thestructure may be described by a Start Volume, a Structure Model Index(SMI) and a Percent Open Cell Content.

The Article has a Star Volume of from about 1 mm³ to about 90 mm³, inone embodiment from about 5 mm³ to about 80 mm³, in another embodimentfrom about 10 mm³ to about 70 mm³, and in still another embodiment fromabout 15 mm³ to about 60 mm³

The Article has a non-negative Structure Model Index of from about 0.0to about 3.0, in one embodiment from about 0.5 to about 2.75, and inanother embodiment from about 1.0 to about 2.50.

To measure the cell interconnectivity via the Star Volume and theStructure Model Index, disk-like samples, approximately 4 cm in diameterand 3 to 7 mm high, are scanned using a micro computed tomography system(μCT80, SN 06071200, Scanco Medical AG). Each sample is imaged whilesitting flat on the bottom of a cylindrical tube. Image acquisitionparameters are 45 kVp, 177 μA, 51.2 mm field of view, 800 ms integrationtime, 1000 projections. The number of slices is adjusted to cover theheight of the sample. The reconstructed data set consisted of a stack ofimages, each 2048×2048 pixels, with an isotropic resolution of 25 μm.For data analysis, a volume of interest is selected to be fully withinthe sample, avoiding the surface region. A typical volume of interest is1028×772×98 voxels.

Structure Model Index (SMI) is measured using Scanco Medical's BoneTrabecular Morphometry evaluation with a threshold of 17. With thisindex the structural appearance of trabecular bone is quantified (see T.Hildebrand, P. Rüegsegger. Quantification of bone microarchitecture withthe structure model index. Comp Meth Biomech Biomed Eng 1997; 1:15-23).The triangulated surface is dilated in normal direction by aninfinitesimal amount, and the new bone surface and volume is calculated.By this, the derivative of the bone surface (dBS/dr) can be determined.The SMI is then represented by the equation:

${SMI} = {6 \cdot \frac{{BV} \cdot \frac{{BS}}{r}}{{BS}^{2}\;}}$

SMI relates to the convexity of the structure to a model type. Ideal(flat) plates have an SMI of 0 (no surface change with dilation of theplates), whereas ideal cylindrical rods have an SMI of 3 (linearincrease in surface with dilation of rods). Round spheres have an SMI of4. Concave structure gives negative dBS/dr, resulting in negative SMIvalues. Artificial boundaries at the edge of the volume of interest arenot included in the calculation and thus suppressed.

In addition to the Scanco Medical Analysis, Star Volume measurements aremade. Star Volume is a measure of the “openness” of the void space in atwo phase structure. By choosing a random uniformly distributed set ofpoints in the phase of interest (in this case the phase of interest isthe void space or air), lines can be extended in random directions fromeach of these points. The lines are extended until they touch theforeground phase. The length of each of these lines is then recorded.The random points have a sampling of 10 in each direction (x/y/z) and ateach point 10 random angles are chosen. If the line extends to theborder of the ROI of interest that line is discarded (only accept linesthat actually intersect with the foreground phase). The final equationis based upon the research entitled Star Volume In Bone Research AHistomorphometric Analysis Of Trabecular Bone Structure Using VerticalSections; Vesterby, A.; Anat Rec.; 1993 February; 235(2):325-334:

${StarVolume} = {\frac{4}{3}{\pi \cdot \frac{\sum{dist}^{3}}{N}}}$

where “dist” is the individual distances and N is the number of linesexamined.

The Article has a Percent Open Cell Content of from about 80% to 100%,in one embodiment from about 85% to about 97.5%, and in anotherembodiment from about 90% to about 95%.

The Percent Open Cell Content is measured via gas pycnometry. Gaspycnometry is a common analytical technique that uses a gas displacementmethod to measure volume accurately. Inert gases, such as helium ornitrogen, are used as the displacement medium. The sample of the Articleis sealed in the instrument compartment of known volume, the appropriateinert gas is admitted, and then expanded into another precision internalvolume. The pressure before and after expansion is measured and used tocompute the sample Article volume. Dividing this volume into the sampleArticle weight gives the gas displacement density.

The Article produced according to the process discussed herein resultsin a more uniform and consistent structure through the thickness of theArticle. Conventional processing techniques generally lead toopen-celled porous structures comprising three distinct regions: anupper region that is closest to the target density (based onextrapolation from the wet processing density), a middle region with asignificantly lower density and larger pores, and a bottom region with ahigher density and thicker cell walls. While not being bound to theory,the central region's lower density and larger pore sizes are believed tobe due to excessive drainage and bubble collapse during the dryingprocess and thereby also contributing to the higher density and thickercell walls of the bottom region due to gravity. Moreover, this latter,more dense, region is believed to serve as a rate limiting barrier forwater ingress into the porous solid upon being wetted by the consumerwhich significantly decreases the dissolution performance.

As such, the process described herein is directed to addressing theseissues.

Method of Manufacture

The Article can be prepared by the process comprising: (1) Preparing apre-mixture comprising surfactant(s), dissolved water soluble polymer,and optionally plasticizer and other optional ingredients; (2) Aeratingthe mixture by introducing a gas into the mixture; (3) Forming theaerated wet mixture into a desired thickness with optionally athree-dimensional mold; (4) Drying the aerated wet mixture to a desiredfinal moisture content (e.g., from about 0.5 to 25% moisture), in anenvironment that is held at about 100° C. to about 150° C.; and (5)optionally cutting the dried solid into one or more shapes.

Preparation of Pre-Mixture

The pre-mixture is generally prepared by mixing the solids of interest,including surfactant(s), dissolved water soluble polymer, optionalplasticizer and other optional ingredients. This can be accomplished byany suitable mixing processes such as batch or continuous mixing. Highshear or static mixing is also suitable. Any process can be envisionedsuch that the polymer is ultimately dissolved in the presence of water,the surfactant(s), optional actives, optional plasticizer, and any otheroptional ingredients including step-wise processing via pre-mix portionsof any combination of ingredients. The viscosity of the pre-mixtureshould fall within the ranges discussed herein at ambient temperatures(25° C.) and the percent solid content should fall within the rangesdiscussed herein.

Optional Continued Heating of Pre-Mixture

Optionally, the pre-mixture is pre-heated immediately prior to theaeration process at above ambient temperature but below any temperaturesthat would cause degradation of the component. In one embodiment, thepre-mixture is kept at above about 40° C. and below about 99° C.,preferably above about 50° C. and below about 95° C., more preferablyabout 60° C. and below about 90° C. In one embodiment, when theviscosity at ambient temperature of the pre-mix is from about 15,000 cpsto about 150,000 cps, the optional continuous heating should be utilizedbefore the aeration step. In an additional preferred embodiment,additional heat is applied during the aeration process to try andmaintain an elevated temperature during the aeration. This can beaccomplished via conductive heating from one or more surfaces, injectionof steam or other processing means.

Without being limited by a theory, the act of pre-heating thepre-mixture before the aeration step provides a means for lowering theviscosity of pre-mixtures comprising higher percent solids content forimproved introduction of bubbles into the mixture and formation of thedesired porous solid structure. Achieving higher percent solids contentis desirable so as to reduce the energy requirements for drying. Theincrease of percent solids, and therefore conversely the decrease inwater level content, and increase in viscosity is believed to affect thebubble drainage from the pre-mixture during the drying step. Thedrainage and evaporation of water from the pre-mixture during drying isbelieved to be critical to the formation of the desired predominantlyopen-celled porous solid structure described herein.

Pre-heating of the pre-mixture enables the manufacture of the desiredfast dissolving porous solid structure from more viscous processingmixtures with higher percent solids levels that would normally produceslow dissolving and predominantly closed celled porous structures. Whilenot being bound to theory, the increased temperature is believed toinfluence controlled bubble drainage from the thin film bubble facingsinto the plateau borders of the three dimensional foam generatingopenings between the bubbles (formation of open-cells) simultaneous tothe solidification of the resulting plateau border structure (driven byevaporation). The demonstrated ability to achieve such inter-connectedopen-celled solid foam architectures with good mechanical integrity andvisual appearance of the Article produced via the present invention andwithout collapse of the “unstable” foam structure during the dryingprocess is surprising. The alternative predominantly closed celledporous solids that are typically produced without the processinginnovations described herein have significantly poorer dissolution anddo not meet the structural parameters encompassed by the porous solidstructure described herein.

Moreover, the higher % solids and viscosity pre-mixtures resulted insolids with significantly less percent (%) shrinkage from the dryingprocess while still resulting in porous solid structure with fastdissolution rates. On the one hand this is intuitive as the higherviscosities during the drying process should serve to mitigate thedrainage and bubble rupture/collapse/coalescence that give rise to theshrinkage. However, on the other hand this is counterintuitive as suchreduced drainage should mitigate the formation of the desiredpredominantly open-celled porous solid structure (with a minimum degreeof cell interconnectivity) during the drying process.

Aeration of Pre-Mixture

The aeration of the pre-mixture is accomplished by introducing a gasinto the pre-mixture, preferably by mechanical mixing energy but alsomay be achieved via chemical means to form an aerated mixture. Theaeration may be accomplished by any suitable mechanical processingmeans, including but not limited to: (i) Batch tank aeration viamechanical mixing including planetary mixers or other suitable mixingvessels, (ii) semi-continuous or continuous aerators utilized in thefood industry (pressurized and non-pressurized), or (iii) spray-dryingthe processing mixture in order to form aerated beads or particles thatcan be compressed such as in a mould with heat in order to form theporous solid.

Less preferred, but also envisioned in aeration with chemical foamingagents by in-situ gas formation (via chemical reaction of one or moreingredients, including formation of carbon dioxide (CO₂ (g)) by aneffervescent system.

In a particular embodiment, it has been discovered that the Article canbe prepared within continuous pressurized aerators that areconventionally utilized within the foods industry in the production ofmarshmallows. Suitable continuous pressurized aerators include theMorton whisk (Morton Machine Co., Motherwell, Scotland), the Oakescontinuous automatic mixer (E. T. Oakes Corporation, Hauppauge, N.Y.),the Fedco Continuous Mixer (The Peerless Group, Sidney, Ohio), and thePreswhip (Hosokawa Micron Group, Osaka, Japan).

Forming the Aerated Wet Pre-Mixture

The forming of the aerated wet pre-mixture may be accomplished by anysuitable means to form the mixture in a desired shape or shapesincluding, but not limited to (i) depositing the aerated mixture tospecially designed moulds comprising a non-interacting and non-sticksurface such as TEFLON®, metal, HDPE, polycarbonate, NEOPRENE®, rubber,LDPE, glass and the like; (ii) depositing the aerated mixture intocavities imprinted in dry granular starch contained in a shallow tray;and (iii) depositing the aerated mixture onto a continuous belt orscreen comprising any non-interacting or non-stick material such asTEFLON®, metal, HDPE, polycarbonate, NEOPRENE®, rubber, LDPE, glass andthe like, the resulting dried product may be later stamped, cut,embossed or stored on a roll. The formation results in a formed aeratedwet pre-mixture.

The wet density range of the aerated pre-mixture ranges from about 0.15g/cm³ to about 0.50 g/cm³, preferably from about 0.20 g/cm³ to about0.45 g/cm³, more preferably from about 0.25 g/cm³ to about 0.40 g/cm³,and even more preferably from about 0.30 g/cm³ to about 0.35 g/cm³.

Drying the Formed Aerated Wet Pre-Mixture

The drying of the formed aerated wet pre-mixture may be accomplished byany suitable drying environment means including, but not limited to (i)drying room(s) including rooms with controlled temperature and pressureor atmospheric conditions; (ii) ovens including non-convection orconvection ovens with controlled temperature and optionally humidity;(iii) Truck/Tray driers, (iv) multi-stage inline driers; (v) impingementovens; (vi) rotary ovens/driers; (vii) inline roasters; (viii) rapidhigh heat transfer ovens and driers; (ix) dual plenum roasters, (x)conveyor driers, and (xi) vacuum drying chambers.

In one embodiment, the drying environment is selected from the groupconsisting of one or more drying rooms, convection ovens, Truck/Traydriers, multi-stage inline driers, impingement ovens/driers, rotaryovens/driers, inline roasters, rapid high heat transfer ovens anddriers, dual plenum roasters, conveyor driers, vacuum drying chambersand combinations thereof, such that the drying environment is between100° C. and 150° C.

Other suitable drying environments include “volumetric heating”techniques using high frequency electromagnetic fields such as MicrowaveDrying and Radio Frequency (RF) Drying. With these techniques, theenergy is transferred electromagnetically through the aerated wetpre-mixture rather than by conduction or convection.

The drying environment is such that the formed aerated wet pre-mixtureis dried to a dry density of from about 0.10 g/cm³ to about 0.40 g/cm³.

In one embodiment, the drying environment is heated to a temperaturebetween 100° C. and 150° C. In one embodiment, the drying temperature isbetween 105° C. and 145° C. In another embodiment, the dryingtemperature is between 110° C. and 140° C. In a further embodiment, thedrying temperature is between 115° C. and 135° C.

It has been found that increasing the surrounding air temperature of thedrying step to about 100° C. to about 150° C. decreases the drying timeof the formed aerated wet pre-mixture in forming the Article whilemaintaining the desired dissolution properties of the Article. It hasbeen found that increasing surrounding air temperature levels fromambient temperature (25° C.) to 40° C. produced a suitable Article, butdrying times to achieve a final moisture contents were several hours(typically requiring overnight drying). Increasing the surrounding airtemperature of the drying step to 75° C. for a period of about 2 hoursto the desired dry density provided an unsuitable Article and producinga denser bottom region including the formation of continuous sticky filmon the bottom surface (adjacent to the mold) of the formed solid withpoorer dissolution. While not being bound to theory, it is believed thatthis denser bottom region and formed continuous film serve as a ratelimiting barrier for water ingress thereby adversely affecting thedissolution performance of the overall porous solid.

Surprisingly, it was found that an increase in the surrounding airtemperature above 75° C. for the drying step to about 100° C. to about150° C. provides acceptable properties for the Article within a 60minute or less time frame while improving the desired dissolutionproperties. This is counter-intuitive given the poorer results observedupon increasing the temperature from 40° C. to 75° C. Moreover, thistemperature range is above the boiling point of water and would therebybe expected to result in water vapour evaporation rates that likelyexceed the rate of water vapour escape from the solid to the surroundingenvironment and resulting in the regional build-up of excessive internalsolid pressure leading to increased expansion/thickness or “humped”cross sections of the resulting material. While not being bound totheory, it is believed that the initial aerated wet foam closed cellscoalesce together during the critical stages of the drying process underthese preferred temperature conditions, creating inter-connectedopen-celled channels extending to the surface of the solid, and therebyenabling the facile escape of the water vapour molecules withoutexcessive pressure build-up and ensuing regional expansion of theresulting solid.

Increases in the drying temperature beyond 150° C. were generally foundby the Applicants to lead to regional solid expansion as well as partialdiscoloration of the solid surface which is indicative of chemicaldecomposition at these elevated temperatures.

In another embodiment, it has been found that Articles according to thepresent invention can be produced with a further improvement in thebottom region by Microwave drying. While not being bound to theory, itis believed that the internal heating afforded by Microwave heatingtechnology helps to mitigate the drainage from the central region intothe bottom region (adjacent to the mold surface) during the dryingprocess and thereby creating a less dense bottom region and an overallstructure with a more uniform density.

Importantly, microwave drying times of less than about 3 minutes resultin undesired regional solid expansion of the Article. While not beingbound to theory, this is believed to be due to water vapour evaporationrates that exceed the rate of water vapour escape from the solid asdescribed herein above. To achieve drying times beyond 3 minutes,Microwave drying is preferably achieved via a low energy densityapplicator such as are available via Industrial Microwave Systems L.L.C(Morrisville, N.C. http://www.industrialmicrowave.com/). In particular,a low energy two wide wave applicators in series microwave applicatorsystem is preferred with two or more low energy applicator regions(about 5 kW). Ideally, the air environment within the low energymicrowave applicator system is at an elevated temperature (typicallyfrom about 35° C. to about 90° C. and preferably from about 40° C. toabout 70° C. and with good circulation so as to facilitate the removalof the resulting humidity.

In one embodiment, the drying time to the desired dry density is fromabout 3 minutes to about 90 minutes, in another embodiment from about 5minutes to about 60 minutes, in another embodiment from about 7 minutesto about 45 minutes. The drying step results in the Article. Dryingtimes of less than about 3 minutes result in undesired regional solidcross-sectional expansion of the resulting Article, whereas drying timesbeyond these values and up to 2 to 3 hours result in excessivedensification of the bottom surface of the Article leading to poorerdissolution. Drying times between 3 hours and 20 hours (overnight) leadto acceptable Articles, but suffer from poorer economics of production.

The drying times that can be achieved via convective drying are betweenabout 10 minutes to about 90 minutes, in another embodiment from about20 minutes to about 60 minutes, and in another embodiment from about 30minutes to about 45 minutes.

The drying times that can be achieved via Microwave drying are betweenabout 3 minutes and about 25 minutes, in another embodiment betweenabout 5 minutes and about 20 minutes, and in another embodiment betweenabout 7 minutes and about 15 minutes.

The resulting Article (dried) may comprise a dry density of from about0.10 g/cm³ to about 0.40 g/cm³, in one embodiment from about 0.11 g/cm³to about 0.30 g/cm³, in another embodiment from about 0.12 g/cm³ toabout 0.25 g/cm³, and in another embodiment from about 0.13 g/cm³ toabout 0.20 g/cm³.

Further Optional Steps

Further optional steps not recited above may be added at any pointduring or after the recited process. Optional ingredients may beimparted during any of the above described four processing steps or evenafter the drying process. Further optional steps may include furtherfinishing steps, such as the addition of heat sensitive materialsincluding but not limited to perfumes and enzymes; cutting of theArticle into a smaller size; puncturing or slitting the Article, furthermanipulation of the Article such a forming a three-dimensional shape,printing, texturizing, mixing the Article into another composition,laminating the Article with another material, packaging the Article andother process steps.

Additional steps that can be used in the present process include cuttingthe resulting Article into smaller sizes, puncturing the Article withneedles or slitting the Article. The size of the Article will dependupon the desired dosage amount of actives, or in this case surfactant.The frequency of perforation or slitting is confined to maintain thestructural integrity of the Article such that it can still be handled.

The Article may be further manipulated into a shape or form other than aflat plane or sheet. Other three-dimensional shapes may includespherical bead or ball, flowers, flower petals, berry shapes and variousknown pasta shapes. As such the process may further include a stepwhereby the Article is manipulated into a three-dimensional shape.

The Article may undergo different manipulation such as being printedupon or texturized by dimpled, waffled or otherwise topographicallypatterned surfaces including letters, logos or figures. The printing ortexturizing of the Article can also be the result of creping processes,imprinted coatings, embossing patterns, laminating to other layershaving raised portions, or the result of the physical form of thedissolvable porous solid substrate itself. The printing step may includeprinting by spraying, knife, rod, kiss, slot, painting, printing such asflexographic (flexo) printing and combinations thereof. Therefore, thepresent process can further include the step of printing or texturingthe Article.

The Article may be utilized by being mixed with other compositions orproducts. The mixing should not detract from the dissolution propertiesherein described. Therefore the present process may further comprise thestep of mixing the Article with another composition, mixing the Articlewith another product.

The Article may be packaged for consumption individually or in aplurality of Articles. The Article may be included in a kit whereinvarious types of products are supplied, including Articles withdifferent compositions, Article(s) with other products making up aregime of series of products for a desired benefit, or Article(s) withother products unrelated such as a toiletry travel kit for travel onairplanes.

Suitable packaging material may be selected such that the Article isprotected from inadvertent exposure to liquids. The packaging materialmay be air and/or vapor permeable, dependent upon the environment inwhich the Article is to be sold.

The process may further include a step of packaging the Articleindividually for sale as a product. The process may further include astep of packaging a plurality of Article for sale as a product. Theprocess may further include a step of including a packaged Article in akit for sale as a product. The packaging step is undertaken after theformation of the Article, preferably after the Article is cut into asuitable size. The Article may be packaged on the same line as theproduction of Article or the Article may be collected, shipped orstored, and then packaged at a later time.

Percent (%) Solids in Pre-Mixture

The processing mixtures of the present invention comprise: from about15% to about 70% solids, in one embodiment from about 30% to about 70%solids, in one embodiment from about 30% to about 60% solids, in oneembodiment from about 32% to about 55% solids, in one embodiment fromabout 34% to about 50%, and in another embodiment from about 36% toabout 45% solids, by weight of the pre-mixture before drying. The %solids content is the summation of the weight percentages by weight ofthe total processing mixture of all of the solid, semi-solid and liquidcomponents excluding water and any obviously volatile materials such aslow boiling alcohols.

Viscosity of Pre-Mixture

At ambient temperature and pressure, the processing mixtures of thepresent invention have a viscosity of from about 2,500 cps to about150,000 cps, in one embodiment from about 15,000 cps to about 150,000cps, in one embodiment from about 20,000 cps to about 125,000 cps, inanother embodiment from about from about 25,000 cps to about 100,000cps, and in still another embodiment from about 30,000 cps to about75,000 cps. The processing mixture viscosity values are measured using aTA Instruments AR500 Rheometer with 4.0 cm diameter parallel plate and1,200 micron gap at a shear rate of 1.0 reciprocal seconds for a periodof 30 seconds at 23° C.

Surfactants

The Article comprises one or more surfactants suitable for applicationto the hair or skin. Surfactants suitable for use in the Article includeanionic surfactants, nonionic surfactants, cationic surfactants,zwitterionic surfactants, amphoteric surfactants, polymeric surfactantsor combinations thereof.

In one embodiment, the Article is a lathering dissolvable solid personalcare product (dried) and comprises from about 23% to about 75% by weightof the Article of surfactant, in one embodiment from about 30% to about70% by weight of the Article of surfactant, in one embodiment from about40% to about 65% by weight of the Article of surfactant. In such cases,the pre-mixture may comprise from about 8% to about 30% by weight of thepre-mixture of surfactant, in one embodiment from about 13% to about 28%by weight of the pre-mixture of surfactant, in one embodiment from about18% to about 25% by weight of the pre-mixture of surfactant.

Non-limiting examples of anionic surfactants suitable for use hereininclude alkyl and alkyl ether sulfates, sulfated monoglycerides,sulfonated olefins, alkyl aryl sulfonates, primary or secondary alkanesulfonates, alkyl sulfosuccinates, acyl taurates, acyl isethionates,alkyl glycerylether sulfonate, sulfonated methyl esters, sulfonatedfatty acids, alkyl phosphates, acyl glutamates, acyl sarcosinates, alkylsulfoacetates, acylated peptides, alkyl ether carboxylates, acyllactylates, anionic fluorosurfactants, sodium lauroyl glutamate, andcombinations thereof.

Preferred anionic surfactants for use in the personal care compositionsinclude ammonium lauryl sulfate, ammonium laureth sulfate, triethylaminelauryl sulfate, triethylamine laureth sulfate, triethanolamine laurylsulfate, triethanolamine laureth sulfate, monoethanolamine laurylsulfate, monoethanolamine laureth sulfate, diethanolamine laurylsulfate, diethanolamine laureth sulfate, lauric monoglyceride sodiumsulfate, sodium lauryl sulfate, sodium laureth sulfate, potassium laurylsulfate, potassium laureth sulfate, sodium lauryl sarcosinate, sodiumlauroyl sarcosinate, lauryl sarcosine, cocoyl sarcosine, ammonium cocoylsulfate, ammonium lauroyl sulfate, sodium cocoyl sulfate, sodium lauroylsulfate, potassium cocoyl sulfate, potassium lauryl sulfate,triethanolamine lauryl sulfate, triethanolamine lauryl sulfate,monoethanolamine cocoyl sulfate, monoethanolamine lauryl sulfate, sodiumtridecyl benzene sulfonate, sodium dodecyl benzene sulfonate, andcombinations thereof.

Amphoteric surfactants suitable for use herein include, but are notlimited to derivatives of aliphatic secondary and tertiary amines inwhich the aliphatic radical can be straight or branched chain andwherein one substituent of the aliphatic substituents contains fromabout 8 to about 18 carbon atoms and one contains an anionic watersolubilizing group, e.g., carboxy, sulfonate, sulfate, phosphate, orphosphonate. Examples include sodium 3-dodecyl-aminopropionate, sodium3-dodecylaminopropane sulfonate, sodium lauryl sarcosinate,N-alkyltaurines such as the one prepared by reacting dodecylamine withsodium isethionate according to the teaching of U.S. Pat. No. 2,658,072,N-higher alkyl aspartic acids such as those produced according to theteaching of U.S. Pat. No. 2,438,091, and the products described in U.S.Pat. No. 2,528,378, and mixtures thereof. The family of amphoacetatesderived from the reaction of sodium chloroacetate with amidoamines toproduce alkanoyl amphoacetates are particularly effective, e.g.lauryolamphoacetate, and the like.

Zwitterionic surfactants suitable for use herein include, but are notlimited to derivatives of aliphatic quaternary ammonium, phosphonium,and sulfonium compounds, in which the aliphatic radicals can be straightor branched chain, and wherein one of the aliphatic substituentscontains from about 8 to about 18 carbon atoms and one substituentcontains an anionic group, e.g., carboxy, sulfonate, sulfate, phosphate,or phosphonate. Other zwitterionic surfactants suitable for use hereininclude betaines, including high alkyl betaines such as coco dimethylcarboxymethyl betaine, cocoamidopropyl betaine, cocobetaine, laurylamidopropyl betaine, oleyl betaine, lauryl dimethyl carboxymethylbetaine, lauryl dimethyl alphacarboxyethyl betaine, cetyl dimethylcarboxymethyl betaine, lauryl bis-(2-hydroxyethyl) carboxymethylbetaine, stearyl bis-(2-hydroxypropyl) carboxymethyl betaine, oleyldimethyl gamma-carboxypropyl betaine, laurylbis-(2-hydroxypropyl)alpha-carboxyethyl betaine, and mixtures thereof.The sulfobetaines may include coco dimethyl sulfopropyl betaine, stearyldimethyl sulfopropyl betaine, lauryl dimethyl sulfoethyl betaine, laurylbis-(2-hydroxyethyl) sulfopropyl betaine and mixtures thereof. Alsosuitable amphoteric surfactants include amidobetaines andamidosulfobetaines, wherein the RCONH(CH₂)₃ radical is attached to thenitrogen atom of the betaine are also useful herein.

Cationic surfactants may include a DEQA compound. The DEQA compoundsencompass a description of diamido actives as well as actives with mixedamido and ester linkages.

Preferred DEQA compounds are typically made by reacting alkanolaminessuch as MDEA (methyldiethanolamine) and TEA (triethanolamine) with fattyacids. Some materials that typically result from such reactions includeN,N-di(acyl-oxyethyl)-N,N-dimethylammonium chloride orN,N-di(acyl-oxyethyl)-N,N-methylhydroxyethylammonium methylsulfatewherein the acyl group is derived from animal fats, unsaturated, andpolyunsaturated, fatty acids (See U.S. Pat. No. 5,759,990 at column 4,lines 45-66). Additional non-limiting examples of such DEQA compoundsare described in U.S. Pat. No. 5,580,481 and U.S. Pat. No. 5,476,597.

Other suitable actives for use as a cationic surfactant include reactionproducts of fatty acids with dialkylenetriamines in, e.g., a molecularratio of about 2:1, said reaction products containing compounds of theformula:

R¹—C(O)—NH—R²—NH—R³NH—C(O)—R¹

wherein R¹, R² are defined as above, and each R³ is a C₁₋₆ alkylenegroup, preferably an ethylene group. Examples of these actives arereaction products of tallow acid, canola acid, or oleic acids withdiethylenetriamine in a molecular ratio of about 2:1, said reactionproduct mixture containing N,N″-ditallowoyldiethylenetriamine,N,N″-dicanola-oyldiethylenetriamine, or N,N″-dioleoyldiethylenetriamine,respectively, with the formula:

R¹—C(O)—NH—CH₂CH₂—NH—CH₂CH₂—NH—C(O)—R¹

wherein R² and R³ are divalent ethylene groups, R¹ is defined above andan acceptable examples of this structure when R¹ is the oleoyl group ofa commercially available oleic acid derived from a vegetable or animalsource, include EMERSOL® 223LL or EMERSOL® 7021, available from HenkelCorporation.

Another active for use as a cationic surfactant has the formula:

[R¹—C(O)—NR—R²—N(R)₂—R³NR—C(O)—R¹]⁺X⁻

wherein R, R¹, R², R³ and X⁻ are defined as above. Examples of thisactive are the di-fatty amidoamines based softener having the formula:

[R¹—C(O)—NH—CH₂CH₂—N(CH₃)(CH₂CH₂OH)—CH₂CH₂—NH—C(O)—R¹]⁺CH₃SO₄ ⁻

wherein R¹—C(O) is an oleoyl group, soft tallow group, or a hardenedtallow group available commercially from Degussa under the trade namesVARISOFT® 222LT, VARISOFT® 222, and VARISOFT® 110, respectively.

A second type of DEQA (“DEQA (2)”) compound suitable as a active for useas a cationic surfactant has the general formula:

[R₃N⁺CH₂CH(YR¹)(CH₂YR¹)]X⁻

wherein each Y, R, R¹, and X⁻ have the same meanings as before.

These types of agents and general methods of making them are disclosedin U.S. Pat. No. 4,137,180, Naik et al., issued Jan. 30, 1979. Anexample of a preferred DEQA (2) is the “propyl” ester quaternaryammonium fabric softener active having the formula1,2-di(acyloxy)-3-trimethylammoniopropane chloride.

In another embodiment, the Article is a substantially non-latheringdissolvable solid personal care product and comprises from about 0% toabout 10% by weight of the Article of an ionic (anionic, zwitterionic,cationic and mixtures thereof) surfactant, in one embodiment from about0% to about 5% by weight of the Article of an ionic surfactant, and inone embodiment from about 0% to about 2.5% by weight of the Article ofan ionic surfactant, and from about 1% to about 50% by weight of theArticle of a nonionic or polymeric surfactant, in one embodiment fromabout 5% to about 45% by weight of the Article of a nonionic orpolymeric surfactant, and in one embodiment from about 10% to about 40%by weight of the Article of a nonionic or polymeric surfactant, andcombinations thereof.

Suitable nonionic surfactants for use in the present invention includethose described in McCutcheion's Detergents and Emulsifiers, NorthAmerican edition (1986), Allured Publishing Corp., and McCutcheion'sFunctional Materials, North American edition (1992). Suitable nonionicsurfactants for use in the personal care compositions of the presentinvention include, but are not limited to, polyoxyethylenated alkylphenols, polyoxyethylenated alcohols, polyoxyethylenatedpolyoxypropylene glycols, glyceryl esters of alkanoic acids,polyglyceryl esters of alkanoic acids, propylene glycol esters ofalkanoic acids, sorbitol esters of alkanoic acids, polyoxyethylenatedsorbitor esters of alkanoic acids, polyoxyethylene glycol esters ofalkanoic acids, polyoxyethylenated alkanoic acids, alkanolamides,N-alkylpyrrolidones, alkyl glycosides, alkyl polyglucosides, alkylamineoxides, and polyoxyethylenated silicones.

In a highly preferred embodiment, the nonionic surfactant selected fromsorbitan esters and alkoxylated derivatives of sorbitan esters includingsorbitan monolaurate (SPAN® 20), sorbitan monopalmitate (SPAN® 40),sorbitan monostearate (SPAN® 60), sorbitan tristearate (SPAN® 65),sorbitan monooleate (SPAN® 80), sorbitan trioleate (SPAN® 85), sorbitanisostearate, polyoxyethylene (20) sorbitan monolaurate (Tween® 20),polyoxyethylene (20) sorbitan monopalmitate (Tween® 40), polyoxyethylene(20) sorbitan monostearate (Tween® 60), polyoxyethylene (20) sorbitanmonooleate (Tween® 80), polyoxyethylene (4) sorbitan monolaurate (Tween®21), polyoxyethylene (4) sorbitan monostearate (Tween® 61),polyoxyethylene (5) sorbitan monooleate (Tween® 81), all available fromUniqema, and combinations thereof.

Suitable polymeric surfactants for use in the personal care compositionsof the present invention include, but are not limited to, blockcopolymers of ethylene oxide and fatty alkyl residues, block copolymersof ethylene oxide and propylene oxide, hydrophobically modifiedpolyacrylates, hydrophobically modified celluloses, silicone polyethers,silicone copolyol esters, diquaternary polydimethylsiloxanes, andco-modified amino/polyether silicones.

Polymer

The one or more water-soluble polymers suitable for the Article hereinare selected such that their weighted average molecular weight is fromabout 40,000 to about 500,000, in one embodiment from about 50,000 toabout 400,000, in yet another embodiment from about 60,000 to about300,000, and in still another embodiment from about 70,000 to about200,000. The weighted average molecular weight is computed by summingthe average molecular weights of each polymer raw material multiplied bytheir respective relative weight percentages by weight of the totalweight of polymers present within the porous solid.

The water-soluble polymer(s) of the Article can include, but are notlimited to, synthetic polymers including polyvinyl alcohols,polyvinylpyrrolidones, polyalkylene oxides, polyacrylates, caprolactams,polymethacrylates, polymethylmethacrylates, polyacrylamides,polymethylacrylamides, polydimethylacrylamides, polyethylene glycolmonomethacrylates, copolymers of acrylic acid and methyl acrylate,polyurethanes, polycarboxylic acids, polyvinyl acetates, polyesters,polyamides, polyamines, polyethyleneimines, maleic/(acrylate ormethacrylate) copolymers, copolymers of methylvinyl ether and of maleicanhydride, copolymers of vinyl acetate and crotonic acid, copolymers ofvinylpyrrolidone and of vinyl acetate, copolymers of vinylpyrrolidoneand of caprolactam, vinyl pyrollidone/vinyl acetate copolymers,copolymers of anionic, cationic and amphoteric monomers, andcombinations thereof.

The water-soluble polymer(s) of the Article may also be selected fromnaturally sourced polymers including those of plant origin examples ofwhich include karaya gum, tragacanth gum, gum Arabic, acemannan, konjacmannan, acacia gum, gum ghatti, whey protein isolate, and soy proteinisolate; seed extracts including guar gum, locust bean gum, quince seed,and psyllium seed; seaweed extracts such as Carrageenan, alginates, andagar; fruit extracts (pectins); those of microbial origin includingxanthan gum, gellan gum, pullulan, hyaluronic acid, chondroitin sulfate,and dextran; and those of animal origin including casein, gelatin,keratin, keratin hydrolysates, sulfonic keratins, albumin, collagen,glutelin, glucagons, gluten, zein, and shellac.

Modified natural polymers are also useful as water-soluble polymer(s) inthe Article. Suitable modified natural polymers include, but are notlimited to, cellulose derivatives such as hydroxypropylmethylcellulose,hydroxymethylcellulose, hydroxyethylcellulose, methylcellulose,hydroxypropylcellulose, ethylcellulose, carboxymethylcellulose,cellulose acetate phthalate, nitrocellulose and other celluloseethers/esters; and guar derivatives such as hydroxypropyl guar.

Preferred water-soluble polymers of the Article include polyvinylalcohols, polyvinylpyrrolidones, polyalkylene oxides, starch and starchderivatives, pullulan, gelatin, hydroxypropylmethylcelluloses,methycelluloses, and carboxymethycelluloses.

More preferred water-soluble polymers of the Article include polyvinylalcohols, and hydroxypropylmethylcelluloses. Suitable polyvinyl alcoholsinclude those available from Celanese Corporation (Dallas, Tex.) underthe CELVOL trade name including, but not limited to, CELVOL 523, CELVOL530, CELVOL 540, CELVOL 518, CELVOL 513, CELVOL 508, CELVOL 504, andcombinations thereof. Suitable hydroxypropylmethylcelluloses includethose available from the Dow Chemical Company (Midland, Mich.) under theMETHOCEL trade name including, but not limited, to METHOCEL E50,METHOCEL E15, METHOCEL E6, METHOCEL E5, METHOCEL E3, METHOCEL F50,METHOCEL K100, METHOCEL K3, METHOCEL A400, and combinations thereofincluding combinations with above mentionedhydroxypropylmethylcelluloses.

The Article (dried) may comprise from about 10% to about 50% by weightof the Article of water soluble polymer, in one embodiment from about15% to about 40% by weight of the Article of water soluble polymer, inone embodiment from about 20% to about 30% by weight of the Article ofwater soluble polymer.

The pre-mixture may comprise from about 3% to about 20% by weight of thepre-mixture of water soluble polymer, in one embodiment from about 5% toabout 15% by weight of the pre-mixture of water soluble polymer, in oneembodiment from about 7% to about 10% by weight of the pre-mixture ofwater soluble polymer.

Plasticizer

The Article may comprise a water soluble plasticizing agent suitable foruse in compositions discussed herein. Non-limiting examples of suitableplasticizing agents include polyols, copolyols, polycarboxylic acids,polyesters and dimethicone copolyols.

Examples of useful polyols include, but are not limited to, glycerin,diglycerin, propylene glycol, ethylene glycol, butylene glycol,pentylene glycol, cyclohexane dimethanol, hexane diol, polyethyleneglycol (200-600), sugar alcohols such as sorbitol, manitol, lactitol andother mono- and polyhydric low molecular weight alcohols (e.g., C₂-C₈alcohols); mono di- and oligo-saccharides such as fructose, glucose,sucrose, maltose, lactose, and high fructose corn syrup solids andascorbic acid.

Examples of polycarboxylic acids include, but are not limited to citricacid, maleic acid, succinic acid, polyacrylic acid, and polymaleic acid.

Examples of suitable polyesters include, but are not limited to,glycerol triacetate, acetylated-monoglyceride, diethyl phthalate,triethyl citrate, tributyl citrate, acetyl triethyl citrate, acetyltributyl citrate.

Examples of suitable dimethicone copolyols include, but are not limitedto, PEG-12 dimethicone, PEG/PPG-18/18 dimethicone, and PPG-12dimethicone.

Other suitable platicizers include, but are not limited to, alkyl andallyl phthalates; napthalates; lactates (e.g., sodium, ammonium andpotassium salts); sorbeth-30; urea; lactic acid; sodium pyrrolidonecarboxylic acid (PCA); sodium hyraluronate or hyaluronic acid; solublecollagen; modified protein; monosodium L-glutamate; alpha & betahydroxyl acids such as glycolic acid, lactic acid, citric acid, maleicacid and salicylic acid; glyceryl polymethacrylate; polymericplasticizers such as polyquaterniums; proteins and amino acids such asglutamic acid, aspartic acid, and lysine; hydrogen starch hydrolysates;other low molecular weight esters (e.g., esters of C₂-C₁₀ alcohols andacids); and any other water soluble plasticizer known to one skilled inthe art of the foods and plastics industries; and mixtures thereof.

Preferred placticizers include glycerin and propylene glycol. EP 0283165B1 discloses other suitable plasticizers, including glycerol derivativessuch as propoxylated glycerol.

The pre-mixture may comprise from about 0.3% to about 8% by weight ofthe pre-mixture of plasticizer, in one embodiment from about 1% to about5% by weight of the pre-mixture of plasticizer, in one embodiment fromabout 2% to about 4% by weight of the pre-mixture of plasticizer.

The Article (dried) may comprise from about 1% to about 25% by weight ofthe Article of plasticizer, in one embodiment from about 3% to about 20%by weight of the Article of plasticizer, in one embodiment from about 5%to about 15% by weight of the Article of plasticizer.

Optional Ingredients

The Article may further comprise other optional ingredients that areknown for use or otherwise useful in compositions, provided that suchoptional materials are compatible with the selected essential materialsdescribed herein, or do not otherwise unduly impair product performance.

Such optional ingredients are most typically those materials approvedfor use in cosmetics and that are described in reference books such asthe CTFA Cosmetic Ingredient Handbook, Second Edition, The Cosmetic,Toiletries, and Fragrance Association, Inc. 1988, 1992.

Emulsifiers suitable as an optional ingredient herein include mono- anddi-glycerides, fatty alcohols, polyglycerol esters, propylene glycolesters, sorbitan esters and other emulsifiers known or otherwisecommonly used to stabilized air interfaces, as for example those usedduring preparation of aerated foodstuffs such as cakes and other bakedgoods and confectionary products, or the stabilization of cosmetics suchas hair mousses.

Further non-limiting examples of such optional ingredients includepreservatives, perfumes or fragrances, coloring agents or dyes,conditioning agents, hair bleaching agents, thickeners, moisturizers,emollients, pharmaceutical actives, vitamins or nutrients, sunscreens,deodorants, sensates, plant extracts, nutrients, astringents, cosmeticparticles, absorbent particles, adhesive particles, hair fixatives,fibers, reactive agents, skin lightening agents, skin tanning agents,anti-dandruff agents, perfumes, exfoliating agents, acids, bases,humectants, enzymes, suspending agents, pH modifiers, hair colorants,hair perming agents, pigment particles, anti-acne agents, anti-microbialagents, sunscreens, tanning agents, exfoliation particles, hair growthor restorer agents, insect repellents, shaving lotion agents,co-solvents or other additional solvents, and similar other materials.

Suitable conditioning agents include high melting point fatty compounds,silicone conditioning agents and cationic conditioning polymers.Suitable materials are discussed in US 2008/0019935, US 2008/0242584 andUS 2006/0217288.

Non-limiting examples of product type embodiments for use by the Articleinclude hand cleansing substrates, hair shampoo or other hair treatmentsubstrates, body cleansing substrates, shaving preparation substrates,fabric care substrate (softening), dish cleaning substrates, pet caresubstrates, personal care substrates containing pharmaceutical or otherskin care active, moisturizing substrates, sunscreen substrates, chronicskin benefit agent substrates (e.g., vitamin-containing substrates,alpha-hydroxy acid-containing substrates, etc.), deodorizing substrates,fragrance-containing substrates, and so forth.

Distance to Maximum Force Method: Measured via a Rupture Method on aTexture Analyzer using a TA-57R cylindrical probe with Texture Exponent32 Software. The Article should have a thickness of between 4 to 7 mmand cut in a circle with a diameter of at least 7 mm for this method; orcarefully cut or stacked to be within this overall thickness anddiameter range. The porous solid sample is carefully mounted on top ofthe cylinder with four screws mounted on top with the top lid affixed inplace on top of the sample. There is a hole in the center of thecylinder and its lid which allows the probe to pass through and stretchthe sample. The sample is measured with a pre-test speed of 1 mm persecond, a test speed of 2 mm per second and a post test speed of 3 mmper second over a total distance of 30 mm. The distance to maximum forceis recorded.Hand Dissolution Method: One Article, with dimensions of approximately43 mm×43 mm×4-6 mm, is placed in the palm of the hand while wearingnitrile gloves. 7.5 cm³ of from about 30° C. to about 35° C. tap wateris quickly applied to the product via syringe. Using a circular motion,palms of hands are rubbed together 2 strokes at a time until dissolutionoccurs (up to 30 strokes). The hand dissolution value is reported as thenumber of strokes it takes for complete dissolution or as 30 strokes asthe maximum.

Lather Profile: Lather Volume

The Article provides a lather profile as described hereafter. The lathervolume assessment is performed on 15 g/10 inch flat Oriental virgin hairswitches that have been treated with 0.098 g of artificial liquid sebum[10-22% olive oil, 18-20% coconut oil, 18-20% oleic acid, 5-9% lanolin,5-9% squalene, 3-6% palmitic acid, 3-6% paraffin oil, 3-6% dodecane,1-4% stearic acid, 1-4% cholesterol, 1-4% coconut fatty acid, 18-20%choleth-24]. The hair switch is rinsed with 9-11 grain, 100° F. water at1.5 gallons/min for 20 seconds with a shower nozzle. For testing theliquid control products, 0.75 cm³ of liquid product are applied to thecenter of the switch, the lower portion of hair on the switch is thenrubbed over the product on the hair 10 times in a circular motion,followed by 40 strokes back and forth (a total of 80 strokes). Latherspeed is recorded as the number of strokes when the first lather isobviously generated during the 80 strokes, Lather from operator's glovesis transferred to a graduated cylinder with a 3.5 cm inside diameter andwith total capacities of either 70 ml, 110 ml, or 140 ml depending onthe total amount of lather generated (height modification of standardsized graduated cylinders via a glass shop). Lather from hair isgathered using one downward stroke on the switch with a tight grip andis also placed into the cylinder. Total lather volume is recorded inmilliliters. Three runs per test sample are performed and the mean ofthe three values is calculated. When testing the Article, 0.20+/−0.01grams of product are weighed with the aid of scissors if required andapplied to the switch and then 2 cm³ of additional water are added tothe product via syringe. The lathering technique is then performed asdescribed for liquid products after a 10 second waiting time.

As used herein, the terms “substantially non-lathering” and“non-lathering” are used to mean a lather volume of from 0 ml to 20 ml.

% Shrinkage

The % shrinkage is computed by subtracting the final measured thicknessfrom the original formed thickness prior to the drying step and dividingby the formed thickness and multiplying by 100 to generate a percentageshrinkage. The latter original formed thickness can be approximated bythe depth of the mold in instances where the wet pre-mixture is appliedlevel to the top of the mold as described herein.

The Article has a maximum Cell Wall Thickness. The Article has a CellWall Thickness of from about from about 0.02 mm to about 0.15 mm, in oneembodiment from about 0.025 mm to about 0.12 mm, in another embodimentfrom about 0.03 mm to about 0.09 mm, and in still another embodimentfrom about 0.035 mm to about 0.06 mm.

The Cell Wall Thickness is computed from the scanned images via a microcomputed tomography system (μCT80, SN 06071200, Scanco Medical AG) asdescribed herein. The Cell Wall Thickness is determined according to themethod defined for the measurement of Trabecular Thickness using ScancoMedical's Bone Trabecular Morphometry evaluation. The definition ofTrabecular Thickness as taken from the Scanco User's manual: TrabecularThickness uses a Euclidean distance transformation (EDM), whichcalculates the Euclidean distance from any point in the foreground tothe nearest background point. The Trabecular Thickness measurerepresents twice the centerline values associated with the local maximaof the EDM, which represents the distance to the center of the object(twice this distance will yield the thickness).

The Article also has a minimum Specific Surface Area. The Article has aSpecific Surface Area of from about 0.03 m²/g to about 0.25 m²/g, in oneembodiment from about 0.035 m²/g to about 0.22 m²/g, in anotherembodiment from about 0.04 m²/g to about 0.19 m²/g, and in still anotherembodiment from about 0.045 m²/g to about 0.16 m²/g.

The Specific Surface Area is measured via a gas adsorption technique.Surface Area is a measure of the exposed surface of a solid sample onthe molecular scale. The BET (Brunauer, Emmet, and Teller) theory is themost popular model used to determine the surface area and is based upongas adsorption isotherms. Gas Adsorption uses physical adsorption andcapillary condensation to measure a gas adsorption isotherm. Thetechnique is summarized by the following steps; a sample is placed in asample tube and is heated under vacuum or flowing gas to removecontamination on the surface of the sample. The sample weight isobtained by subtracting the empty sample tube weight from the combinedweight of the degassed sample and the sample tube. The sample tube isthen placed on the analysis port and the analysis is started. The firststep in the analysis process is to evacuate the sample tube, followed bya measurement of the free space volume in the sample tube using heliumgas at liquid nitrogen temperatures. The sample is then evacuated asecond time to remove the helium gas. The instrument then beginscollecting the adsorption isotherm by dosing krypton gas at userspecified intervals until the requested pressure measurements areachieved. Samples may then analyzed using an ASAP 2420 with krypton gasadsorption. It is recommended that these measurements be conducted byMicromeretics Analytical Services, Inc. (One Micromeritics Dr, Suite200, Norcross, Ga. 30093). More information on this technique isavailable on the Micromeretics Analytical Services web sites(www.particletesting.com or www.micromeritics.com), or published in abook, “Analytical Methods in Fine particle Technology”, by Clyde Orr andPaul Webb.

The Article is preferably a flat, flexible substrate in the form of apad, a strip or tape and having a thickness of from about 0.5 mm toabout 10 mm, in one embodiment from about 1 mm to about 9 mm, in anotherembodiment from about 2 mm to about 8 mm, and in a further embodimentfrom about 3 mm to about 7 mm as measured by the below methodology. Inthe case of cylindrical, spherical, or other objects with more of athird dimension versus a pad or strip, the thickness is taken as themaximum distance of the shortest dimension, i.e., the diameter of asphere or cylinder for instance, and the thickness ranges are the sameas described above.

The thickness of the dissolvable porous solid (i.e., substrate or samplesubstrate) is obtained using a micrometer or thickness gage, such as theMitutoyo Corporation Digital Disk Stand Micrometer Model NumberIDS-1012E (Mitutoyo Corporation, 965 Corporate Blvd, Aurora, Ill., USA60504). The micrometer has a 1 inch diameter platen weighing about 32grams, which measures thickness at an application pressure of about 40.7psi (6.32 gm/cm²).

The thickness of the dissolvable porous solid is measured by raising theplaten, placing a section of the sample substrate on the stand beneaththe platen, carefully lowering the platen to contact the samplesubstrate, releasing the platen, and measuring the thickness of thesample substrate in millimeters on the digital readout. The samplesubstrate should be fully extended to all edges of the platen to makesure thickness is measured at the lowest possible surface pressure,except for the case of more rigid substrates which are not flat. Formore rigid substrates which are not completely flat, a flat edge of thesubstrate is measured using only one portion of the platen impinging onthe flat portion of the substrate.

The Article has a basis weight of from about 400 grams/m² to about 3,000grams/m², in one embodiment from about 500 grams/m² to about 2,500grams/m², in another embodiment from about 600 grams/m² to about 2,000grams/m², and in still another embodiment from about 700 grams/m² toabout 1,500 grams/m².

The Basis Weight of the dissolvable porous solid component of thepersonal care composition herein is calculated as the weight of thedissolvable porous solid component per area of the selected dissolvableporous solid (grams/m²). The area is calculated as the projected areaonto a flat surface perpendicular to the outer edges of the poroussolid. For a flat object, the area is thus computed based on the areaenclosed within the outer perimeter of the sample. For a sphericalobject, the area is thus computed based on the average diameter as3.14×(diameter/2)². For a cylindrical object, the area is thus computedbased on the average diameter and average length as diameter×length. Foran irregularly shaped three dimensional object, the area is computedbased on the side with the largest outer dimensions projected onto aflat surface oriented perpendicularly to this side. This can beaccomplished by carefully tracing the outer dimensions of the objectonto a piece of graph paper with a pencil and then computing the area byapproximate counting of the squares and multiplying by the known area ofthe squares or by taking a picture of the traced area (preferablyshaded-in for contrast) including a scale and using image analysistechniques.

The Article has a dry density of from about 0.08 g/cm³ to about 0.30g/cm³, in one embodiment from about 0.10 g/cm³ to about 0.25 g/cm³, andin another embodiment from about 0.12 g/cm³ to about 0.20 g/cm³.

The dry density of the dissolvable porous solid is determined by theequation: Calculated Density=Basis Weight of porous solid/(Porous SolidThickness×1,000). The Basis Weight and Thickness of the dissolvableporous solid are determined in accordance with the methodologiesdescribed herein.

Scanning Electron Microscope (SEM) Imaging:

Representative sections were cut from the sponge with a clean razorblade and mounted with the cut face up on a standard cryo-SEM stub.Samples were secured onto the stub with carbon tape and silver paint.Samples were imaged using an Hitachi S-4700 FE-SEM fitted with a GatanAlto 2500 cryo stage. Samples were cooled to −95 dC before imaging inthe microscope. Samples were lightly coated with Platinum to reducecharging. Representative images were collected at 2 kV, 20 uA extractionvoltage, ultra high resolution mode using the lower secondary electrondetector. Long working distances were used to allow the entire sample tobe imaged in one frame.

EXAMPLES

The following examples further describe and demonstrate embodimentswithin the scope of the present invention. The examples are given solelyfor the purpose of illustration and are not to be construed aslimitations of the present invention, as many variations thereof arepossible without departing from the spirit and scope of the invention.All exemplified amounts are concentrations by weight of the totalcomposition, i.e., wt/wt percentages, unless otherwise specified.

Examples 1-12 Surfactant/Polymer Liquid Processing Compositions

The following surfactant/polymer liquid processing compositions areprepared at the indicated weight percentages as described below. Theliquid formulations differ on the ratio of anionic:amphotericsurfactant, the type of amphoteric surfactant, and the type of anionicsurfactants:

TABLE 1 Component Ex. 1 Ex. 2 Ex. 3 Weight Percent Solids 28.1% 28.9%29.5% Anionic:Amphoteric (Zwitterionic) Ratio 100:0 80:20 60:40 Glycerin3.0 3.0 3.0 Polyvinyl alcohol¹ 7.4 7.4 7.4 Sodium Lauroamphoacetate (26%activity)² 0.0 14.6 29.2 Ammonium Laureth-3 sulfate (25% activity) 7.56.0 4.5 Ammonium Undecyl sulfate (24% activity) 30.3 24.3 18.2 AmmoniumLaureth-1 sulfate (70% activity) 12.1 9.7 7.2 Citric Acid 0.04 0.6 1.0Distilled water 39.7 34.4 29.5 Total 100.0 100.0 100.0 pH 6.1 6.4 6.1Viscosity (cp) 5,300 8,200 14,500 ¹Sigma-Aldrich Catalog No. 363081, MW85,000-124,000, 87-89% hydrolyzed ²McIntyre Group Ltd, University Park,IL, Mackam HPL-28ULS

TABLE 2 Component Ex. 4 Ex. 5 Ex. 6 Weight Percent Solids 33.0% 36.0%39.0% Anionic:Amphoteric (Zwitterionic) Ratio 60:40 60:40 60:40 Glycerin3.35 3.66 3.96 Polyvinyl alcohol¹ 8.27 9.02 9.77 SodiumLauroamphoacetate (26% activity)² 32.64 35.60 38.57 Ammonium Laureth-3sulfate (25% activity) 5.03 5.49 5.94 Ammonium Undecyl sulfate (24%activity) 20.34 22.19 24.04 Ammonium Laureth-1 sulfate (70% activity)8.05 8.78 9.51 Citric Acid 1.12 1.22 1.32 Distilled water 21.20 14.046.88 Total 100.0 100.0 100.0 pH 6.6 6.7 6.7 Viscosity (cp) 23,900 37,60050,900 ¹Sigma-Aldrich Catalog No. 363081, MW 85,000-124,000, 87-89%hydrolyzed ²McIntyre Group Ltd, University Park, IL, Mackam HPL-28ULS

TABLE 3 Component Ex. 7 Ex. 8 Ex. 9 Ex. 10 Weight Percent Solids 30.1%33.3% 35.2% 37.2% Anionic:Amphoteric 60:40 60:40 60:40 60:40(Zwitterionic) Ratio Glycerin 3.0 3.2 3.4 3.6 Polyvinyl alcohol¹ 7.4 8.18.6 9.0 Sodium Lauroamphoacetate 29.2 31.8 33.7 35.6 (26% activity)²Ammonium Laureth-3 sulfate 4.5 4.9 5.2 5.5 (25% activity) AmmoniumUndecyl sulfate 18.2 19.9 21.1 22.2 (24% activity) Ammonium Laureth-1sulfate 7.3 8.0 8.4 8.9 (70% activity) Cationic guar polymer³ 0.50 0.500.53 0.56 Citric Acid 0.95 1.6 1.7 1.8 Distilled water 28.95 22.0 17.412.8 Total 100.0 100.0 100.0 100.0 pH 6.4 5.7 5.5 5.4 Viscosity (cp)19,200 32,200 52,400 64,900 ¹Sigma-Aldrich Catalog No. 363081, MW85,000-124,000, 87-89% hydrolyzed ²McIntyre Group Ltd, University Park,IL, Mackam HPL-28ULS ³Jaguar C-500, available from Rhodia Inc.(Cranbury, New Jersey)

TABLE 4 Component Ex. 11 Ex. 12 Weight Percent Solids 30.1% 33.3%Anionic:Amphoteric (Zwitterionic) Ratio 60:40 60:40 Glycerin 3.0 3.2Polyvinyl alcohol¹ 7.4 8.1 Sodium Lauroamphoacetate (26% activity)² 29.231.8 Ammonium Laureth-3 sulfate (25% activity) 4.5 4.9 Ammonium Undecylsulfate (24% activity) 18.2 19.9 Ammonium Laureth-1 sulfate (70%activity) 7.3 8.0 Cationic cellulose³ 0.50 0.5 Citric Acid 0.95 1.6Distilled water 28.95 22.0 Total 100.0 100.0 pH 6.1 5.8 Viscosity (cp)19,600 35,400 ¹Sigma-Aldrich Catalog No. 363081, MW 85,000-124,000,87-89% hydrolyzed ²McIntyre Group Ltd, University Park, IL, MackamHPL-28ULS ³UCARE ™ Polymer LR-400, available from Amerchol Corporation(Plaquemine, Louisiana)

A target weight of 300 grams, for each of the above compositions, isprepared with the use of a conventional overhead stirrer (IKA® RW20DZMStirrer available from IKA® Works, Inc., Wilmington, Del.) and a hotplate (Corning Incorporated Life Sciences, Lowell, Mass.). Into anappropriately sized and cleaned vessel, the distilled water and glycerinare added with stirring at 100-150 rpm. The cationic polymer, whenpresent, is then slowly added with constant stirring until homogenous.The polyvinyl alcohol is weighed into a suitable container and slowlyadded to the main mixture in small increments using a spatula whilecontinuing to stir while avoiding the formation of visible lumps. Themixing speed is adjusted to minimize foam formation. The mixture isslowly heated to 75° C. to 80° C. after which surfactants are added. Themixture is then heated to 85° C. while continuing to stir and thenallowed to cool to room temperature. Additional distilled water is addedto compensate for water lost to evaporation (based on the original tareweight of the container). The final pH is between 5.2-6.6 and adjustedwith citric acid or diluted sodium hydroxide if necessary. The resultingprocessing mixture viscosity is measured.

Examples 13-15 Dissolving Porous Shampoo Solids andPerformance/Structural Data: Faster Drying and Anionic:Amphoteric RatioStudy

The dissolving porous shampoo solid Examples 13, 14, and 15 wereprepared from the surfactant/polymer liquid processing solutions fromExamples 1, 2, and 3, respectively, as described below. Each example iscomprised of 4 versions evaluating two processing variables at high andlow values, namely the density (0.26 and 0.32 grams/cm³ aerated wetdensities) and the drying temperature (one condition consisting ofdrying the Articles for 30 minutes in a 75° C. oven followed by dryingovernight in a 40° C. oven versus the second condition consisting ofdrying the Articles for 30 to 45 minutes in a 130° C. oven).

TABLE 5 Ex. Ex. Ex. Ex. 13.1 13.2 13.3 13.4 Liquid Processing (Ex. 1)(Ex. 1) (Ex. 1) (Ex. 1) Composition (Ex.) Anionic:Amphoteric 100:0 100:0100:0 100:0 % Solids 28.1% 28.1% 28.1% 28.1% Viscosity (cp) 5,300 5,3005,300 5,300 Cationic polymer None None None None Aeration Time (sec) 3525 35 25 Wet Density (g/cm³) 0.26 0.32 0.26 0.32 Oven Temperature (° C.)130 130 75/40^(a) 75/40^(a) Drying Time (min) 42 49 1140 1140 Averagedry Article 0.87 1.03 0.80 0.95 weight (g) Average dry Article 0.52 0.520.47 0.48 thickness (cm) Average dry Article 0.10 0.12 0.10 0.12 density(g/cm³) Average basis weight (g/m²) 520 610 470 560 ^(a)Articles storedin first oven held at 75° C. for 30 minutes and then second oven held at40° C. overnight (14 hours).

TABLE 6 Ex. Ex. Ex. Ex. 14.1 14.2 14.3 14.4 Liquid Processing (Ex. 2)(Ex. 2) (Ex. 2) (Ex. 2) Composition (Ex.) Anionic:Amphoteric 80:20 80:2080:20 80:20 % Solids 28.9% 28.9% 28.9% 28.9% Viscosity (cp) 8,200 8,2008,200 8,200 Cationic polymer None None None None Aeration Time (sec) 7665 75 64 Wet Density (g/cm³) 0.26 0.32 0.26 0.32 Oven Temperature (° C.)130 130 75/40^(a) 75/40^(a) Drying Time (min) 46 46 1210 1210 Averagedry Article 0.94 1.08 0.89 0.89 weight (g) Average dry Article 0.53 0.490.49 0.46 thickness (cm) Average dry Article 0.10 0.13 0.11 0.11 density(g/cm³) Average basis weight (g/m²) 560 640 530 530 ^(a)Articles storedin first oven held at 75° C. for 30 minutes and then second oven held at40° C. overnight (14 hours).

TABLE 7 Ex. Ex. Ex. Ex. 15.1 15.2 15.3 15.4 Liquid Processing (Ex. 3)(Ex. 3) (Ex. 3) (Ex. 3) Composition (Ex.) Anionic:Amphoteric 60:40 60:4060:40 60:40 % Solids 29.5% 29.5% 29.5% 29.5% Viscosity (cp) 14,50014,500 14,500 14,500 Cationic polymer None None None None Aeration Time(sec) 125 95 120 85 Wet Density (g/cm³) 0.26 0.32 0.26 0.32 OvenTemperature (° C.) 130 130 75/40^(a) 75/40^(a) Drying Time (min) 39 471170 1170 Average dry Article 0.99 1.06 0.91 1.09 weight (g) Average dryArticle 0.52 0.50 0.48 0.48 thickness (cm) Average dry Article 0.11 0.130.11 0.13 density (g/cm³) Average basis weight (g/m²) 580 630 540 650^(a)Articles stored in first oven held at 75° C. for 30 minutes and thensecond oven held at 40° C. overnight (14 hours).

250 grams of the surfactant/polymer liquid processing solution (fromExamples 1 through 3) is transferred into a 5 quart stainless steel bowlof a KITCHENAID® Mixer Model K5SS (available from Hobart Corporation,Troy, Ohio) and fitted with a flat beater attachment. The mixture isvigorously aerated at a maximum speed setting of 10 until a wet densityof approximately 0.26 grams/cm³ or 0.32 grams/cm³ is achieved (timesrecorded in table). The density is measured by weighing a filling a cupwith a known volume and evenly scraping off the top of the cup with aspatula. The resulting aerated mixture is then spread with a spatulainto square 160 mm×160 mm aluminum molds with a depth of 6.5 mm with theexcess wet foam being removed with the straight edge of a large metalspatula that is held at a 45° angle and slowly dragged uniformly acrossthe mold surface. The aluminum molds are then placed into a 75° C.convection oven for approximately 30 minutes and then immediatelytransferred into a 40° C. convection oven for overnight. Alternatively,the aluminum molds may be placed into a 130° C. convection oven forapproximately 35 to 45 minutes until the weight loss due to evaporationis between 67% and 69% of the original foam weight within each mold. Themolds are allowed to cool to room temperature with the substantially dryporous solids removed from the molds with the aid of a thin spatula andtweezers.

Each of the resulting 160 mm×160 mm square pads is cut into nine 43mm×43 mm squares (with rounded edges) using a cutting die and a SamcoSB20 cutting machine (each square representing surface area ofapproximately 16.9 cm²). The resulting smaller pads are thenequilibrated overnight (14 hours) in a constant environment room kept at70° F. and 50% relative humidity within large zip-lock bags that areleft open to the room atmosphere. Each pad is then weighed and placed onan individual weight boat with the original mold side facing downward.The average pad weights are recorded.

Dissolution and Lather Volume:

The below tables summarize the hand dissolution and lather volumeperformance data from the dissolvable porous solid shampoos of Examples13 through 15. The data was collected by the methods as describedherein.

TABLE 8 Dissolution/Lather Performance from Lower Density Articles(prepared from 0.26 wet density foams) Drying Anionic: Temper-Amphoteric ature Dry Density Hand Lather Example Ratio (° C.)(grams/cm³) Dissolution Volume Ex. 13.1 100:0  130 0.10 12 strokes  90ml Ex. 13.3 100:0  75/40¹ 0.10 >30 strokes  85 ml Ex. 14.1  80:20 1300.10 10 strokes 100 ml Ex. 14.3  80:20 75/40¹ 0.11 20 strokes 105 ml Ex.15.1  60:40 130 0.11 4 strokes 140 ml Ex. 15.3  60:40 75/40¹ 0.11 14strokes 120 ml ¹Articles stored in first oven held at 75° C. for 30minutes and then second oven held at 40° C. overnight (14 hours)

TABLE 9 Dissolution/Lather Performance from Higher Density Articles(prepared from 0.32 wet density foams) Drying Anionic: Temper-Amphoteric ature Dry Density Hand Lather Example Ratio (° C.)(grams/cm³) Dissolution Volume Ex. 13.2 100:0  130 0.12 >30 strokes  75ml Ex. 13.4 100:0  75/40¹ 0.12 >30 strokes  80 ml Ex. 14.2  80:20 1300.13 14 strokes 105 ml Ex. 14.4  80:20 75/40¹ 0.11 28 strokes 100 ml Ex.15.2  60:40 130 0.13 4 strokes 125 ml Ex. 15.4  60:40 75/40¹ 0.13 30strokes 120 ml ¹Articles stored in first oven held at 75° C. for 30minutes and then second oven held at 40° C. overnight (14 hours)

The above two data sets on both the higher and lower density poroussolids comprising differing anionic: amphoteric surfactant ratiosdemonstrate single variably improved dissolution performance among theArticles that are dried at the higher temperature and for a shorter timeperiod (130° C. for 30 to 45 minutes) relative to the Articles that aredried at the lower temperature and for a longer time period (75° C. for30 minutes followed by 40° C. overnight). While not being bound totheory, this is believed to be due to the formation of a more opencelled structure with a resulting higher available surface area fordissolution upon being diluted with water. Additionally, the above twodata sets demonstrate single variably improved dissolution and latherperformance from the Articles produced from the surfactant systems witha higher proportion of amphoteric surfactant.

Structural Characterization:

The below tables summarize the structural measurements taken on thehigher and lower density porous solids from Examples 13, 14 and 15produced from two differing drying temperatures and comprising thediffering anionic:amphoteric ratios. SEM and micro-CT images were alsotaken for the lower density Articles and are referenced in the attachedfigures. The data was collected by the methods as described herein.

TABLE 10 Structural Measurements from Lower Density Articles (preparedfrom 0.26 wet density foams) Kr BET Micro-CT Micro-CT Surface PycnometryCell Wall Star Micro-CT Area % Open thickness Volume SMI SEM CT Example(m²/g) Cells (mm) (mm³) Index Image Image Ex. 13.1 0.096 91.0% 0.041 7.52.3 FIG. 1a FIG. 2a Ex. 13.3 0.079 89.7% 0.086 13.4 1.2 FIG. 1b FIG. 2bEx. 14.1 0.047 90.7% 0.050 11.1 2.4 FIG. 1c FIG. 2c Ex. 14.3 0.030 92.1%0.089 10.8 1.5 FIG. 1d FIG. 2d Ex. 15.1 0.051 92.0% 0.062 5.7 2.4 FIG.1e FIG. 2e Ex. 15.3 0.039 93.6% 0.088 12.3 1.5 FIG. 1f FIG. 2f

TABLE 11 Structural Measurements from Lower Density Articles (preparedfrom 0.32 wet density foams) Kr BET Micro-CT Micro-CT Surface PycnometryCell Wall Star Micro-CT Area % Open thickness Volume SMI μCT Example(m²/g) Cells (mm) (mm³) Index Image Ex. 13.2 0.073 89.1% 0.044 8.5 2.2FIG. 3a Ex. 13.4 0.050 90.5% 0.088 10.2 1.1 FIG. 3b Ex. 14.2 0.044 90.6%0.047 4.4 2.5 FIG. 3c Ex. 14.4 0.036 89.4% 0.080 4.7 1.2 FIG. 3d Ex.15.2 0.049 92.4% 0.060 7.2 2.4 FIG. 3e Ex. 15.4 0.033 88.3% 0.084 12.21.6 FIG. 3f

The above two data sets on both the higher and lower density poroussolids comprising differing anionic:amphoteric surfactant ratiosdemonstrate single variably increased BET specific surface areas,decreased Cell wall thicknesses, and higher SMI Index values among theArticles that are dried at the higher temperature and for a shorter timeperiod (130° C. for 30 to 45 minutes —See Examples 13.1, 14.1, 15.1,13.2, 14.2 and 15.2) relative to the Articles that are dried at thelower temperature and for a longer time period (75° C. for 30 minutesfollowed by 40° C. overnight approx. 14 hours—See Examples 13.3, 14.3,15.3, 13.4, 14.4 and 15.4). Specifically, one can see 22% to 57%increased BET surface areas, 29% to 52% reduced Cell Wall thicknesses,and SMI Index values that are 1 unit higher by comparing across similarcompositions and densities (See Examples 13.1 vs. 13.3, 14.1 vs. 14.3,15.1 vs. 15.3, 13.2 vs. 13.4, 14.2 vs. 14.4, and 15.2 vs. 15.4). The SEMand Micro-CT images are qualitatively consistent with this data (SeeFIGS. 1 a vs. 1 b, 1 c vs. 1 d, 1 e vs. 1 f, 2 a vs. 2 b, 2 c vs. 2 d, 2e vs. 2 f, 3 a vs. 3 b, 3 c vs. 3 d, and 3 e vs. 3 f).

In several instances the Articles dried at the lower temperaturesexhibit increased Star Volumes and % Open Cells. While not being boundto theory, this is believed to be due to increased drainage and bubblecoalescence in the inner volume region (the selected region for theMicro-CT computations) which leads to a denser lower region that isbelieved to serve as a rate limiting barrier for water diffusion andrapid dissolution. This phenomenon can be observed qualitatively byviewing the Middle Cross-section and Bottom Cross-section SEM images(See FIGS. 1 a vs. 1 b, 1 c vs. 1 d, and 1 e vs. 1 f) as well as theInterior Volume and Full Volume Micro-CT images (See FIGS. 2 a vs. 2 b,2 c vs. 2 d, 2 e vs. 2 f, 3 a vs. 3 b, 3 c vs. 3 d, and 3 e vs. 3 f).

Examples 16-19 Dissolving Porous Shampoo Solids and Performance Data:Liquid Processing % Solids and Viscosity Study

The dissolving porous shampoo solid Examples 16, 17, 18, and 19 wereprepared from the surfactant/polymer liquid processing solutions fromExamples 3, 4, 5, and 6, respectively, and according to the sameprocedure as described for Examples 13 through 15 (employing a 130° C.drying temperature for 30-45 minutes). These porous solid examples areproduced from liquid processing compositions with identical componentsand in identical polymer:surfactant:placticizer ratios, the onlydifference being the level of water giving rise to increasing % solidsand corresponding increasing processing mixture viscosities. For theliquid processing compositions with higher % solids and viscosities,extended aeration times are explored in an attempt to achieve therequisite density range of the present invention.

TABLE 12 Ex. Ex. Ex. Ex. 16 17.1 17.2 17.3 Liquid Processing (Ex. 3)(Ex. 4) (Ex. 4) (Ex. 4) Composition (Ex.) Anionic:Amphoteric 60:40 60:4060:40 60:40 (Zwitterionic) % Solids 29.5% 33.0% 33.0% 33.0% Viscosity(cp) 14,500 23,900 23,900 23,900 Cationic polymer None None None NoneAeration Time (sec) 125 105 140 155 Wet Density (g/cm³) 0.26 0.38 0.330.35 Oven Temperature (° C.) 130 130 130 130 Drying Time (min) 40 52 4552 Average dry pad 0.99 1.54 1.27 1.35 weight (g) Average dry pad 0.520.43 0.46 0.51 thickness (cm) Average dry pad 0.11 0.21 0.16 0.16density (g/cm³) Average basis weight (g/cm²) 580 910 750 800

TABLE 13 Ex. 18.1 Ex. 18.2 Ex. 18.3 Ex. 19 Liquid Processing (Ex. 5)(Ex. 5) (Ex. 5) (Ex. 6) Composition (Ex.) Anionic:Amphoteric 60:40 60:4060:40 60:40 (Zwitterionic) % Solids 36.0% 36.0% 36.0% 39.0% Viscosity(cp) 37,600 37,600 37,600 51,000 Cationic polymer None None None NoneAeration Time (sec) 100 150 360 480 Wet Density (g/cm³) 0.44 0.40 0.380.52 Oven Temperature (° C.) 130 130 130 130 Drying Time (min) 55 50 6085 Average dry pad 1.75 1.81 1.63 2.73 weight (g) Average dry pad 0.500.52 0.53 0.53 thickness (cm) Average dry pad 0.21 0.21 0.18 0.31density (g/cm³) Average basis weight (g/cm²) 1040 1070 960 1600

The above table demonstrates the technical difficulty in achieving therequisite density and basis weight range of the present invention athigher % solids and viscosity levels. In particular, increasing the %solids level from 29.5% to 33% resulted in a viscosity increase from14,500 cps to 23,900 cps. In this instance, increasing the aeration timeis successful in achieving a desired lower density resulting in a lowerwet and dry density limit of approximately 0.33 g/cm³ and 0.16 g/cm³,respectively (See Example 16 vs. Examples 17.1, 17.2, and 17.3).Increasing the % solids level further to 36% resulted in a viscosity of37,600 cps. Increasing the aeration time to 380 seconds was only able toachieve a resulting lower wet and dry density of approximately 0.38g/cm³ and 0.18-0.21 g/cm³, respectively (See Examples 18.1, 18.2 and18.3). A further increase in % solids level to 39% resulted in aviscosity of 51,000 cps with a resulting lower wet and dry density limitof approximately 0.52 g/cm₃ and 0.31 g/cm³, respectively (See Example19). It has generally been found that viscosities of below 30,000 cpsare required to achieve the open-celled solids with the definedrequisite wet and dry densities of the present invention withconventional processing as is demonstrated above.

Dissolution Performance:

The below tables summarize the hand dissolution performance data fromthe dissolvable porous solid shampoos of Examples 16 through 19. Thedata was collected by the methods as described herein.

TABLE 14 Viscosity Aeration Dry Density Hand Example % Solids (cp) Time(sec) (grams/cm³) Dissolution Ex. 16 29.5% 14,500 125 0.11 4 strokes Ex.17.1 33.0% 23,900 105 0.21 16 strokes Ex. 17.2 33.0% 23,900 140 0.17 14strokes Ex. 17.3 33.0% 23,900 155 0.16 6 strokes Ex. 18.1 36.0% 37,600100 0.21 30 strokes Ex. 18.2 36.0% 37,600 150 0.21 30 strokes Ex. 18.336.0% 37,600 360 0.18 24 strokes Ex. 19 39.0% 51,000 480 0.31 >30strokes

The above table demonstrates an upper limit on liquid processing mixture% solids and viscosity level in order to achieve fast dissolving porousstructures of the present invention (according to conventionalprocessing). In particular, the liquid processing mixtures with 36% and39% solids levels and corresponding high viscosities resulted in poroussolids with poor dissolution performance (See Examples 18.1, 18.2, 18.3and 19). In contrast, the liquid processing mixtures with 29.5% and33.0% solids levels and corresponding lower viscosities resulted inporous solids with good dissolution performance (less than 20 strokes).Examples 16 through 19 demonstrate the inherent technical difficulty ofachieving fast dissolving porous solids of the present invention athigher % solids and viscosity levels based on conventional processing.

Examples 20-26 Dissolving Porous Shampoo Solids—Hot Vs. AmbientProcessing

The dissolving porous shampoo solid Examples 20-26 are prepared from thesurfactant/polymer liquid processing solutions from Examples 7, 8, 9,10, 11 and 12, respectively. The examples designated as “AmbientProcessing” conditions are prepared according to the same procedure asdescribed for Examples 13 through 19 (employing a 130 degrees Celsiusdrying temperature for 30-45 minutes). The examples designated as “HotProcessing” conditions are made in the same manner except that theliquid processing mixture is pre-heated to 70° C. before aeration and a70-75° C. hot water jacket is employed around the 5 quart stainlesssteel bowl of the KITCHENAID® Mixer Model K5SS (available from HobartCorporation, Troy, Ohio) during the aeration part of the process (alsoemploying a 130° C. drying temperature for 30-45 minutes). The poroussolid examples within each Table are produced from liquid processingcompositions with identical components and in the samepolymer:surfactant:placticizer ratios, the only difference being thelevel of water giving rise to increasing % solids and correspondingincreasing processing mixture viscosities. Examples 20 through 24comprise a cationic guar polymer and examples 25 and 26 comprise acationic cellulose polymer.

TABLE 15 Ex. 20.1 Ex. 20.2 Ex. 21.1 Ex. 21.2 Liquid Processing (Ex. 7)(Ex. 7) (Ex. 8) (Ex. 8) Composition (Ex.) Anionic:Amphoteric 60:40 60:4060:40 60:40 (Zwitterionic) % Solids 30.1% 30.1% 33.3% 33.3% Viscosity(cp) 19,200 19,200 32,200 32,200 Cationic polymer Guar Guar Guar GuarProcessing Conditions Ambient Ambient Ambient Ambient Aeration Time(sec) 105 160 105 150 Wet Density (g/cm³) 0.32 0.29 0.38 0.32 OvenTemperature (° C.) 130 130 130 130 Drying Time (min) 49 40 47 40 Averagedry pad 1.08 0.94 1.42 1.21 weight (g) Average dry pad 0.41 0.40 0.480.45 thickness (cm) Average pad shrinkage (%)   37%   38%   27%   30%Average dry pad 0.16 0.14 0.18 0.16 density (g/cm³) Average basis weight(g/cm²) 640 550 840 720

TABLE 16 Ex. 21.3 Ex. 22 Ex. 23 Ex. 24 Liquid Processing Composition(Ex. 8) (Ex. 8) (Ex. 9) (Ex. 10) (Ex.) Anionic:Amphoteric 60:40 60:4060:40 60:40 (Zwitterionic) % Solids 33.3% 33.3% 35.2% 37.2% Viscosity(cp) 32,200 32,200 52,400 64,900 Cationic polymer Guar Guar Guar GuarProcessing Conditions Ambient Hot Hot Hot Aeration Time (sec) 240 75 80100 Wet Density (g/cm³) 0.31 0.28 0.26 0.32 Oven Temperature (° C.) 130130 130 130 Drying Time (min) 45 41 40 45 Average dry pad weight (g)1.21 1.21 1.25 1.56 Average dry pad thickness (cm) 0.47 0.57 0.60 0.55Average pad shrinkage (%)   28%   12%   8%   16% Average dry pad density(g/cm³) 0.15 0.13 0.12 0.17 Average basis weight (g/cm²) 720 720 740 920

TABLE 17 Ex. 25 Ex. 26 Liquid Processing Composition (Ex.) (Ex. 11) (Ex.12) Anionic:Amphoteric (Zwitterionic) 60:40 60:40 % Solids 30.1% 33.3%Viscosity (cp) 19,600 35,400 Cationic polymer Cellulose CelluloseProcessing Conditions Ambient Hot Aeration Time (sec) 120 130 WetDensity (g/cm³) 0.27 0.26 Oven Temperature (° C.) 130 130 Drying Time(min) 42 38 Average dry pad weight (g) 0.92 1.07 Average dry padthickness (cm) 0.44 0.58 Average pad shrinkage (%)   32%   12% Averagedry pad density (g/cm³) 0.12 0.11 Average basis weight (g/cm²) 550 630

Dissolution Performance:

The below tables summarize the hand dissolution performance data fromthe dissolvable porous solid shampoos of Examples 20 through 25. Thedata was collected by the methods as described herein.

TABLE 18 Aeration Dry Visc. Process. Time Density % Hand Example %Solids (cp) Condit. (sec) (g/cm³) Shrinkage Dissolution Ex. 20.1 30.1%19,200 Ambient 105 0.16 37% 10 strokes Ex. 20.2 30.1% 19,200 Ambient 1600.14 38%  8 strokes Ex. 21.1 33.3% 32,200 Ambient 105 0.18 27% 24strokes Ex. 21.2 33.3% 32,200 Ambient 150 0.16 30% 14 strokes Ex. 21.333.3% 32,200 Ambient 240 0.15 28% 12 strokes Ex. 22 33.3% 32,200 Hot 750.13 12%  9 strokes Ex. 23 35.2% 52,400 Hot 80 0.12  8%  8 strokes Ex.24 37.2% 64,900 Hot 100 0.17 16% 10 strokes Ex. 25 30.1% 19,600 Ambient120 0.12 32%  9 strokes Ex. 26 33.3% 35,400 Hot 130 0.11 12%  6 strokes

The above examples demonstrates the use of the optional pre-heating stepin the processing technique described above which enables the flexibledissolving porous solid structures prepared from pre-mixtures withhigher % solids and viscosity levels (at 25° C.). In particular, rapiddissolving structures (6 to 10 strokes) were achieved with % solidslevels ranging from 33.3% to 37.2% and viscosities ranging from 32,200cps to 64,900 cps (at 25° C.) (See Examples 22, 23, 24, and 26).

These hot processed Articles demonstrate equal to better dissolutionperformance relative to the conventional processing of more diluteliquid processing mixtures with lower viscosities (at 25° C.) (SeeExamples 20.1, 20.2, 21.1, 21.2 and 21.3). This is in marked contrast tothe above described examples 18 and 19 based on conventional processingtechniques wherein solids levels of 36% to 39% and viscosities of 37,600cps to 51,000 cps (at 25° C.) resulted in slowly dissolving solids (24to >30 strokes). Additionally, the optional pre-heating process stepresults in Articles that under go significantly less pad shrinkageduring the drying process (about 8% to about 16% versus conventionalabout 27% to about 38%) giving rise to improve pad appearance andproperties.

Structural Characterization:

The below table summarize the structural measurements taken on theporous solids from Examples 21, 22 and 24 as representative examples forboth ambient and hot processing conditions. The data was collected bythe methods as described herein.

TABLE 19 Structural Measurements Comparing Ambient versus Hot ProcessingKr BET Micro-CT Micro-CT Surface Pycnometry Cell Wall Star Micro-CTProcess Area % Open thickness Volume SMI SEM μCT Ex. Condit. (m²/g)Cells (mm) (mm³) Index Image Image Ex. 21.1 Ambient 0.036 87.1% 0.0941.5 2.2 FIG. 4a FIG. 5a Ex. 21.2 Ambient 0.037 92.3% 0.070 3.9 2.0 FIG.4b FIG. 5b Ex. 22 Hot 0.043 89.8% 0.065 3.6 2.0 FIG. 4c FIG. 5c Ex. 24Hot 0.047 89.8% 0.075 2.5 1.2 FIG. 4d FIG. 5d

One can see from the above examples that the Articles produced by hotprocessing (pre-heating the premixture) of processing mixtures with high% solids levels (33% and 37%) and corresponding high viscosities (32,200cps and 64,900 cps) result in porous structures with greater BETSpecific Surface Areas representing an average 22% increase in surfacearea (See Examples 21.1 and 21.2 vs. Examples 22 and 24). One can alsosee that even the Article produced from a processing mixture with 37%solids and 64,900 cps viscosity (Example 24) exhibits structuralparameters (% Open Cells, Cell Wall Thickness, Star Volume and SMIIndex) within the scope of the present invention. The SEM and Micro-CTimages are qualitatively consistent with this data (See FIGS. 4 a and 4b vs. FIGS. 4 c and 4 d and See FIGS. 5 a and 5 b vs. FIGS. 5 c and 5d).

Example 27 Dissolving Porous Shampoo Solid—Microwave Drying

An identical surfactant-polymer premix is prepared as described inExample 2 and aerated in accordance with the details given in thepreparation of the Article from Example 14.1 to give Example 27.However, unlike Example 14.1 which is dried within a convection oven at130° C., Example 27 is dried within a low energy density microwaveapplicator operated at a power of 2.0 kW and a belt speed of 1 foot perminute and a surrounding air temperature of 130° C. The microwave dryingis conducted on equipment provided by Industrial Microwave Systems Inc.(North Carolina). The resulting Article is compared to Example 14.1 inthe below table:

TABLE 20 Ex. 14.1 Ex. 27 Liquid Processing Composition (Ex. 2) (Ex. 2)(Ex.) Anionic:Amphoteric 80:20 80:20 % Solids 28.9% 28.9% Viscosity (cp)8,200 8,200 Cationic polymer None None Aeration Time (sec) 76 75 WetDensity (g/cm³) 0.26 0.26 Drying Method Convection Oven Low EnergyDensity Microwave Drying Conditions 130° C. Air temp. 2.0 kW 54.4° C.Air temp. Drying Time (min) 46 12 Average dry Article weight (g) 0.940.89 Average basis weight (g/cm²) 560 530The performance data on these two Articles comparing convection ovendrying to microwave drying are given in the below table.

TABLE 21 Dissolution/Lather Performance from Microwave vs. ConvectionOven Drying (prepared from 0.26 wet density foams) Anionic: DryingAmphoteric Drying Time Hand Lather Example Ratio Method (min)Dissolution Volume Ex. 14.1 80:20 Convection 46 10 strokes 100 ml OvenEx. 27 80:20 Microwave 12  6 strokes 107 mlThe structural measurements on these two Articles comparing convectionoven drying to microwave drying are given in the below table.

TABLE 22 Structural Measurements Comparing Ambient versus Hot ProcessingKr BET Micro-CT Micro-CT Surface Pycnometry Cell Wall Star Micro-CT Area% Open thickness Volume SMI SEM μCT Example (m²/g) Cells (mm) (mm³)Index Image Image Ex. 14.1 0.047 90.7% 0.050 11.1 1.9 FIG. 6a FIG. 7aEx. 27 0.046 91.2% 0.050 0.95 2.4 FIG. 6b FIG. 7b

From Tables 21 and 22 it can be seen that microwave drying offersimprovements in drying time and dissolution rate. Moreover, from Table23 it can be seen that the Microwave drying produces Articles with thedesired structural parameters within the range of the present invention.One notable difference is the significantly reduced Star Volume from theMicrowave drying. While not being bound to theory, this is believed tobe due to a more even cross-sectional structure arising from thesimultaneous internal structure Microwave heating versus the initialsurface heating of convection drying. This should help to avoid the lessdense (and more open) central region and more dense (less open) bottomregion formed during convection drying from the premature drainage fromthe central region driven by gravity. Indeed, this can readily beobserved from the SEM and Micro-CT images (See FIGS. 6 a vs. 6 b andFIGS. 7 a vs. 7 b) where it can be seen that the Microwave dried Article27 results in a more homogenous porous structure through the thicknessof the Article.

Note that any actives and/or compositions disclosed herein can be usedin and/or with the articles, and in particular the household carearticles, disclosed in the following U.S. patent applications, includingany publications claiming priority thereto: U.S. 61/229,981; U.S.61/229,986; U.S. 61/229,990; U.S. 61/229,996; U.S. 61/230,000; and U.S.61/230,004. Such articles may comprise one or more of the following:detersive surfactant; plasticizer; enzyme; suds suppressor; sudsbooster; bleach; bleach stabilizer; chelant; cleaning solvent;hydrotrope; divalent ion; fabric softener additive (e.g. quaternaryammonium compounds); nonionic surfactant; perfume; and/or a perfumedelivery system. Such articles may be utilized in methods including, butnot limited to: dosing into a washing machine to clean and/or treatfabric; dosing into a dishwasher to clean and/or treat cutlery; anddosing into water to clean and/or treat fabric and/or hard surfaces.

The dimensions and values disclosed herein are not to be understood asbeing strictly limited to the exact numerical values recited. Instead,unless otherwise specified, each such dimension is intended to mean boththe recited value and a functionally equivalent range surrounding thatvalue. For example, a dimension disclosed as “40 mm” is intended to mean“about 40 mm.”

Every document cited herein, including any cross referenced or relatedpatent or application, is hereby incorporated herein by reference in itsentirety unless expressly excluded or otherwise limited. The citation ofany document is not an admission that it is prior art with respect toany invention disclosed or claimed herein or that it alone, or in anycombination with any other reference or references, teaches, suggests ordiscloses any such invention. Further, to the extent that any meaning ordefinition of a term in this document conflicts with any meaning ordefinition of the same term in a document incorporated by reference, themeaning or definition assigned to that term in this document shallgovern.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A personal care article in the form of a flexibledissolvable porous solid structure, comprising: a. from about 1% toabout 75% surfactant; b. from about 10% to about 50% water solublepolymer; and c. optionally, from about 1% to about 25% plasticizer; andwherein said article has a dry density of from about 0.10 g/cm³ to about0.40 g/cm³, in one embodiment from about 0.11 g/cm³ to about 0.30 g/cm³,in another embodiment from about 0.12 g/cm³ to about 0.25 g/cm³, and inanother embodiment from about 0.13 g/cm³ to about 0.20 g/cm³.
 2. Thepersonal care article of claim 1 wherein the article comprises acellular interconnectivity defined by having a Star Volume of from about1 mm³ to about 90 mm³; and a Structure Model Index that is non-negativeand ranges from about 0.0 to about 3.0.
 3. The personal care article ofclaim 1 wherein the article comprises a surface area of from about 0.03m²/g to about 0.25 m²/g.
 4. The personal care article of claim 1 whereinthe article comprises a % open cells of from about 80% to about 100%. 5.The personal care article of claim 1 wherein the article comprises acell wall thickness of from about 0.02 mm to about 0.15 mm.
 6. Thepersonal care article of claim 1 wherein the article comprises adistance to maximum force value of from about 6 mm to about 30 mm,preferably from about 7 mm to about 25 mm, more preferably from about 8mm to about 20 mm, and even more preferably from about 9 mm to about 15mm.
 7. The personal care article of claim 1 wherein the articlecomprises basis weight of from about 125 grams/m² to about 3,000grams/m².
 8. The personal care article of claim 1 that is lathering andcomprises from about 23% to about 75% by weight of the article of ananionic surfactant.
 9. The personal care article of claim 1 that issubstantially non-lathering and comprises: i. from about 0% to about 10%of an ionic surfactant, ii from about 1% to about 50% of a non-ionicsurfactant or a polymeric surfactant, and iii combinations thereof. 10.The personal care article of claim 9 wherein the nonionic surfactant issorbitan esters and alkoxylated derivatives of sorbitan esters
 11. Thepersonal care article of claim 1 wherein the article comprises a one ormore water-soluble polymers selected from the group comprising polyvinylalcohols, polyvinylpyrrolidones, polyalkylene oxides, polyacrylates,caprolactams, polymethacrylates, polymethylmethacrylates,polyacrylamides, polymethylacrylamides, polydimethylacrylamides,polyethylene glycol monomethacrylates, polyurethanes, polycarboxylicacids, polyvinyl acetates, polyesters, polyamides, polyamines,polyethyleneimines, maleic/(acrylate or methacrylate) copolymers,copolymers of methylvinyl ether and of maleic anhydride, copolymers ofvinyl acetate and crotonic acid, copolymers of vinylpyrrolidone and ofvinyl acetate, copolymers of vinylpyrrolidone and of caprolactam, vinylpyrollidone/vinyl acetate copolymers, copolymers of anionic, cationicand amphoteric monomers, and combinations thereof.
 12. The personal carearticle of claim 1 wherein the article comprises a plasticizer selectedfrom the group comprising glycerol, propylene glycol, butylenes glycol,cyclohexane dimethanol and C₂-C₈ alcohols, alkyl and allyl phthallates,napthalates and esters of C₂-C₁₀ alcohols and acids, and mixturesthereof.